Stark or shocking would describe what I found this morning on a shoot yesterday using the Mini 4.6K in firmware 4.8.

Normally I’m shooting CinemaDNG raw and when I bring the clips into Resolve (prior to using 15.1.2), they look very bad in the Media Page. But when I add the clips to the Media Pool with my ACEScct settings, they look decent and easy to grade.

Yesterday’s footage was shot ProRes 444 and looks quite good in the Media Page and shocking in the Media Pool when using ACEScct. All I did was switch to Resolve YRGB (15.1.2, not Colour Managed) and the clips in the Media Pool now look quite good before I do any grading.

I’m not sure what to conclude. My camera hasn’t changed, but ACES is now useless for me apparently with the only change possibly being the move to 15.1.2. Maybe I’ll find something wrong that I did. I can spend more time investigating later.

John Paines wrote:The differences between the normalization which occurs with the BMPCC 4K log to video or extended video LUTs and RCM can be quite stark.It might be helpful if somebody at BMD explained the differences, and the preferred workflow...?

It would be really good if they did.

I've been patiently waiting for that or for enough pro users to get their cameras to have an active discussion of work flow regarding everything to do with Gen 4 color science, Extended Video, BMPCC 4k luts...

It would be good for them to put together a white paper on it and/or get invloved here with the discussion.

FWIW and given our schedule and workflow, we've been shooting everything in ProRes HQ and bringing it directly into FCPX because it's the native codec and it's a no brainer for fast client turn around.

I've been experimenting with different ways to get the most out of the Film log ProRes footage that is very different from footage and therefore LUTs/workflow from our other BM cameras.

Jamie, I thought I had done everything as I had done before Resolve 15.1.2. You know I’ve had very good success with ACEScct and use of Log primaries, for quite awhile now. I moved on to simple Resolve YRGB to grade the ProRes 444 video yesterday.

Thanks for the suggestions. Feeling a bit of a crunch due to other activities and just taking the path of least resistance this time.

Steps are different with cDNG v ProRes. It may have been setting the IDT automatically in raw, while in ProRes you’d need to set it manually on clips in Media Pool or set IDT project wide in Color Management

CaptainHook wrote:Can you show examples of the differences and explain your setup/workflow?RCM is easy to get wrong and not have the right settings, but there's also a chance of an issue somewhere.

Here's the log version, followed by log+P4k Film to Extended Video v4 LUT applied on the Color page, followed by the RCM version, with BM P4K Pocket Film selected as in the input colorspace in the Media Pool, and rec. 709 2.4 set as both timeline and output. Other settings on that page are left at the defaults.

It's understood that the RCM version isn't actually clipping, but the question is, where's the best place to start?

John Paines wrote:It's understood that the RCM version isn't actually clipping, but the question is, where's the best place to start?]

Oh, that's really a preference question and a case of finding what works best for you. Using RCM and 709 might require more work to pull the range back in how you'd like, but you may prefer the primaries and starting point. Alternatively you may prefer extended video and again you can adjust things pre/post LUT (or CST plugin) to taste.

http://www.captainhook.co.nz/blackmagic-cinema-camera-lut/

**Any post by me prior to Aug 2014 was before i started working for Blackmagic**

Well, the issue is the desire for highest accuracy -- the manual claims that RCM is better math. Is it?

I've stuck with RCM so far, generally preferring it, but have also worked on high contrast clips where the extended video v4 LUT solved problems instantly, that took a lot of pushing and pulling in RCM.

John Paines wrote:Well, the issue is the desire for highest accuracy -- the manual claims that RCM is better math. Is it?

Its less about that, and more about a LUT needing interpolation for values in-between the defined lattice points and that it can/will clip data if it goes beyond the limits. Extended Video is fairly straight forward and should be totally fine at 33^3 with tetrahedral interpolation (change the default in Resolve project settings) so in this particular case I think you can choose the workflow that best suits how you want to work and not worry about which has more accuracy.

Hopefully Extended Video for the other cameras will come to RCM/CST in a future Resolve release soon so if you prefer RCM you will be able to stick with that.

http://www.captainhook.co.nz/blackmagic-cinema-camera-lut/

**Any post by me prior to Aug 2014 was before i started working for Blackmagic**

Yes, ACES always requires an IDT defined by the camera manufacturer, so we are completely reliant on BMD for these from their cameras (same goes for Sony, Red, Panny, etc.), and the IDT has to correspond to the version of the color matrix the clips were recorded with. So, if you shot ProRes to BMD 4.6K Film v3, you need to use the IDT for BMD 4.6K Film v3, and if you recorded in the new v4, then you’ll need the v4 IDT, etc.

As for making LUTs that mimic ACES transforms to use for monitoring, just setup your intended input and output in Resolve and then profile it using the TrimLUT to create the LUT. You can find instructions for how to do that on page 118 of the most recent Resolve manual.

Also worth nothing is that, in my experience, ACES works best when fed raw source footage or lightly compressed 12bit 444 source files. So, I’d stick to BRAW or ProRes4444 if you’re planning to grade in ACES.

I concur with Jamie’s recommendation, although there’s no ProRes 444 on the BMPCC4K. I’ll likely experiment shooting 4K ProRes 422 HQ and then in post transcoding to 2K ProRes 444 prior to grading. And compare that to shooting raw and BRAW Q0 when available.

Since Resolve pulls everything into 32bit float anyway, that transcode isn't going to yield any advantage in terms of bit depth or latitude for grading. If you plan to delete the original cameras files, it would, however, save you some drive space : )

Jamie, yes; since ProRes is compressed, you are probably right that 422 won’t yield 444 at half resolution. Makes more sense that I should shoot raw 3:1 4K and transcode that in post to ProRes 444 2K (for improved storage).

Hello everyone, I'm having some troubles trying to grade the P4K ProRes Film files, I've set RCM to BMD Pocket 4k film the input color space and Rec.709 both timeline and output color space, but when I try to lower the lift setting the brighter parts of the image get even brighter. Is it supposed to work this way or am I missing something?

Rickiriva wrote: when I try to lower the lift setting the brighter parts of the image get even brighter

When you drag lift down, are you actually seeing the absolute level of the highlights go up on the waveform? That would not be expected behavior.

If you lower lift, the brightest parts of the image should be mostly unaffected. By lowering lift, you are increasing contrast in the image, so relative to the shadows the highlights will appear brighter even though their absolute brightness hasn't gone up. I'd bet this is actually what you're seeing.

Rickiriva wrote: when I try to lower the lift setting the brighter parts of the image get even brighter

When you drag lift down, are you actually seeing the absolute level of the highlights go up on the waveform? That would not be expected behavior.

If you lower lift, the brightest parts of the image should be mostly unaffected. By lowering lift, you are increasing contrast in the image, so relative to the shadows the highlights will appear brighter even though their absolute brightness hasn't gone up. I'd bet this is actually what you're seeing.

No, it's the actual rgb parade that shows this weird behaviour, and that's why I was concerned about a possible incorrect setting in the RCM page.

As noted above, there have been instances where the primary wheels behave as if they were actually different controls -- for example, the gain control behaves like the offset control. Or the lift control behaves like the contrast control, and you will indeed see highlights rising when it's lowered.

In my case, this occurred with certain clips, and not with others, also using RCM with BMPCC 4K clips. Hard to know what's going on, since it's unpredictable and usually not present.

I use ACEScct with log primary controls almost exclusively and notice some (unexpected) shift in the waveform that I use 100% of the time when grading. I never considered that a problem though as I’m using the controls to get an end result and I’m not presuming to know how it should work since BMD are the experts.

Rickiriva wrote:No, it's the actual rgb parade that shows this weird behaviour, and that's why I was concerned about a possible incorrect setting in the RCM page.

I tested a bunch of 4K Pocket clips in ACES and in RCM and can't replicate that behavior. Can you post a video screen capture showing both the primary controls adjustment and the RGB parade so we can see the issue?

Rickiriva wrote:No, it's the actual rgb parade that shows this weird behaviour, and that's why I was concerned about a possible incorrect setting in the RCM page.

I tested a bunch of 4K Pocket clips in ACES and in RCM and can't replicate that behavior. Can you post a video screen capture showing both the primary controls adjustment and the RGB parade so we can see the issue?

The only way I managed to share with you the video was by creating a Dropbox link to the file, hope it helps.

You mean the camera? No, it's an apparent Resolve bug. Just out of curiosity, what happens if you leave every other value on the RCM page at the default (no saturation mapping, nits, etc.)? So you just set input space, timeline, output.

John Paines wrote:You mean the camera? No, it's an apparent Resolve bug. Just out of curiosity, what happens if you leave every other value on the RCM page at the default (no saturation mapping, nits, etc.)? So you just set input space, timeline, output.

EDIT: if you can, link to a sample clip where you're seeing it.

The previous post has a link attached to a screen recording where it's noticeable.

John Paines wrote:I mean provide an actual camera clip from the BMPCC 4K to download, where you're seeing this behavior.

The other thing you could try is to turn off RCM and use a LUT (if you want) instead. And see if the same thing happens.

Oh sorry, I didn't understand your request properly, here's a link with a clip straight out of the camera. It's a bit overexposed and I found out that this strange thing occurs after a bit of pushing and pulling, trying to have a satisfying image.https://www.dropbox.com/s/lz044pxb32b8t ... 7.mov?dl=0

I'm seeing the behavior you've noted, on this clip, though how obvious it becomes depends on prior adjustments. You'll also note that if you use the gain control, everything will move -- it's functioning like the offset wheel.